In a bowl, dissolve yeast in water. Add 1 1/2 cups of flour, the oil and sugar. Beat for 3 minutes to make a smooth batter. Gradually stir in enough of the remaining flour, about 1 cup, to form a soft dough. Knead until smooth and satiny about 5 minutes, adding flour as needed to avoid sticking. Place dough in a greased bowl, turn to grease top. Cover and let rise in warm place until doubles, about 1 hour.

Punch dough down, turn onto floured board and divide into 12 pieces. Shape each piece into a smooth ball by gently kneading. Then roll each into a smooth rope about 18" long, and twist into a pretzel shape. Place slightly apart on a greased baking sheet at least 12 by 15 inches, turning loose ends underneath. Let rise, uncovered, until puffy, about 25 minutes.

Meanwhile in 3 quart stainless steel pan (don't use aluminum), bring soda water mixture to boiling; keep water boiling gently. With a slotted spatula, lower one pretzel at a time into pan. Let simmer for 10 seconds on each side, then lift from water, drain briefly on spatula, and return to baking sheet. Let dry briefly, then sprinkle with coarse salt and let stand, uncovered until all have been simmered.

Bake in preheated 425 degree oven for 12 to 15 minutes until golden brown. Transfer to racks.
May be frozen and reheated at 400 degrees for 10 minutes.